Conversion of petroleum oils



Aug. 29, 1944. w. A. SMITH 2,356,952

CONVERSION OF PETROLEUM OILS Filed Jan. 13, 19 12 COOL ING F/PAC 77mmT/NG I A MED IUM TOWER i CONDENSER OVERHEAD REACT/0N 0/? FLASH CHAMBERHEA TING (O/L 44/170 ar 0/1. /va ACTIVATED 22 5:152 s cm )1 mm 0,?(w/vomsn r5) W 7 ll 00 T r/lva a/waso AUX/L/ARY Assn/r H07 6:4355 I 4 iA? pump STE/1M (Am/v5 o/e /X wmq- GASflLE/VE) 7 X7 Z6 M/VE/VTOIQ. WATERof 7- m M cur arm/4cm!) 2 g V 5 Patented Aug. 29, 1944 UNITED STATESPATENT OFFICE 12 Claims.

This invention relates to the conversion, by controlled heat treatment,of petroleum oils into refined components with superior physicalcharacteristics, which refined components may be separated according totheir different boiling temperatures.

This invention is an improvement upon, and continuation in part of, myprior copending application Ser. No. 302,927, filed November 4, 1939.

One object of the invention is to improve the conversion of petroleumoils. Another object of the invention is to provide an improved methodof controlled conversion and/or cracking of hydrocarbons, such aspetroleum oil, which may be carried out by relatively simple andinexpensive apparatus, with which the overhead products obtained willhave improved viscosity index, improved physical characteristics, withwhich one may obtain if desired a maximum possible proportion of lightbodied lubricants of high quality, and a minimum proportion of lessdesirable heavy bodied oils, and which will be relatively simple,practical and efiicient.

Other objects and advantages will appear from the following descriptionof some practical applications of the invention, and the novel featureswill be particularly pointed out hereinafter in connection with theappended claims.

Under the proper temperature and contact time relationships, lubricatingoil bases are selectively cracked and rearranged to yield lubricatingoils .having more desirable physical properties. This is eflectedaccording to this invention, by subjecting the lubricating oil bases toreaction with acid activated clays under the proper temperatures andcontact time conditions. Where the lubricating oil base containsdeactivating components, such, for example, as sulphur, certain metalliccompounds in small quantities are useful for neutralizing thedeactivating properties of the undesirable components, and therebysubstantially increase the activity of the acid ac tivated clay.

The acid activated clay permits degradation and separation ofundesirable fractions and an non-solventized, is effected by this means.

case or bearings, because of the lower internal friction of the oilitself. Additives have been developed to improve, or raise the viscosityindex but such materials in the quantities'specified, according to someliterature published in connec- 15 tion with such a commercial additive,had substantially no efiect on flash, pour, carbon, color,

or other physical characteristics of the oil,

Additives of this type are usually added to the oils which initiallyhave been improved by selective solvent extraction of the more desirablecomponents, and to eliminate as large a proportion as possible of thatportion having the unde-.- sired characteristics, but no improvement inthe physical characteristics of the selected components is achieved bysolvent extraction. On the contrary, actual physical improvement of theuseful parts of the oil is achieved by the control of treatmentpermitted by the proper application of acid activated clay, either aloneor in connection with proper amounts of auxiliary agents in finelydivided form, such as metallic oxides or other chemicals of which copperoxide and aluminum oxide are common examples; the particular auxiliaragent is selected in accordance with the requirements of the materialitself, so

that entirely new substances with markedly improved physicalcharacteristics are obtained, with more or less complete elimination ofundesirable or unstable compounds. Improvement in oils from naphthenicsources, both solventized and quality, it is well known that crude oilsseldom contain lubricating components in the desired relationship tomarketability. For example, Pennsylvania crude oil contains roughlytwice as much heavy residual lubricating oil as it does of the so-calledneutral or volatile lubricating component, yet the normal market demandfrom automobile and truck trade is for relatively light bodiedlubricants containing a high proportion of light lubricating oil. Attimes the demand for heavy Pennsylvania residual oil is so small as tomake the value of this oil to the refiner only slightly higher than thatof fuel oil from much cheaper crudes, resulting in loss of revenue bothto the refiner and the crude oil producer.

According to this invention the conversion and/or cracking of petroleumoils, and particularly the heavy bodied oils, can be effectivelycontrolled and greater yield of the desirable components such as lightbodied oils, obtained by performing the conversion and/or cracking inthe presence of acid activated clay. The clay is, of course, in finelydivided form and preferably fresh or unspent, or reactivated. It ismixed with the oil to be converted preferably while the latter is wellbelow the natural cracking temperature of that oil, such as below 400F'., and where an auxiliary agent in finely divided form is employed, itcan be mixed with the clay and the mixture dispersed throughout the oilbefore the oil reaches the cracking temperature. The oil plus claymixture is then subjected to cracking or conversion conditions andtemperature. It is important for best results that the oil be inintimate contactwith the acid activated clay before the conversionstarts. If the oil is heated approximately to the conversion or crackingtemperature before being brought in contact with the clay, or there isno intimate mixture of the clay and the oil, the clay may be unable toeffect satisfactory and complete control of the conversion, with theresult that too much of the wrong fractions or components is producedand not enough of the more desirable components, such as the lightbodied lubricants. The cracking or conversion temperature to which thebase oil is heated will depend on various factors, such as the sourceand. character of the oil and the nature of the catalyst employed, whichfactors are well understood in this industry. By way of example, in theapparatus shown, temperatures of 800 F. to 890 F. in the transfer lineand of 565 F. to 740 F. in the base of tower section I were employed toproduce satisfactory results in treating Pennsylvania 600 S. R. oil.

Different oils require variations as to treatment, such as for example,quantities of activated clay, chemical modifiers, temperatures, time ofreaction, and desired end results. Such variables must be determinedexperimentally. To enable those experienced in the art readily to apply.7

the invention without undue experimentation, the data elsewhere hereinconcerning results obtained from the treatment of dewaxed Pennsylvania600 steam refined stock are indicative.

In the accompanying drawing, the single figure is a schematic diagram ofa simple system for performing this invention, which has beensuccessfully operated.

In the drawing, the heavy bodied oil or crude oil to be treated is mixedwith the acid-activated clay and placed in a tank or reservoir I0, andif an auxiliary agent is to be employed, it may also be mixed in finelydivided form with the clay and the oil, so that the agent and the claywill be dispersed as much as possible throughout or suspended in, theoil to produce a pumpable mixture.

The mixture of the oil with the clay and agent dispersed therethrough iswithdrawn from the tank I 0 through a conduit ll, controlled by a valveor gate l2, by means of a pump l3, and this pump delivers a stream ofthis mixture through conduit Hi to the lower end of a heating coil l5,which coil passes upwardly through a heating chamber I6. The upper endof the coil I5 is connected by a conduit or pipe I! also called atransfer line, to the upper end of a reaction or flash chamber I8 whichis disposed vertically in a heating chamber l 9 that communicates withthe heating chamber l6 by an aperture 20 in a partition 2| which dividesthe chambers l6 and I9 from one another. Hot gases are supplied to thelower end of the chamber. IS in any suitable manner, such as through apipe or conduit 22 and after rising in the chamber l6, they pass throughopening 20 in partition 2| to the upper end of the chamber I9, and thenthe gases descend to an outlet flue pipe or conduit 23 leading to theSmokestack. The distribution of gas travel is controlled by damper 24 inconduit 23, by valve 24a controlling opening 20; and valve 40 in pipe39.

The showing of the direction of movement of the heating gases relativelyto the oil and clay mixture is merely schematic, and actually theirrelative direction of movement will be largely opposite to one anotheraccording to counterflow principles and good engineering design tosecure the most efficient heat exchange.

The bottom of the reaction or flash chamber [8 is provided with anoutlet pipe 25 controlled by valve 26 through which the bottoms andsuspended clay and any auxiliary agent, that is, the heavy residual oilin which the clay and agent are carried, are removed. These bottoms withclay are removed to any suitable reservoir for subsequent treatment toremove the clay and agent and to utilize the oil component of themixture.

Frequently steam or vacuum can be used to facilitate the removal ofvolatile products, or lighter petroleum fractions can be used,particularly where a change in the character of the lighter fractions isdesired. Recycling of lighter petroleum fractions enables the treatmenton these fractions to be carried to any desired point, in spite of thefact that their vaporization characteristics might otherwise limit thefeasible time and temperature relationship. In this way, long continuedtreatment of even gasoline fractions at temperatures of 500 F. or higheris possible, and the desired molecular changes achieved.

In this particular apparatus, as shown, steam under pressure may beadmitted through pipe 21 into the lower end of the reaction or flashchamber 18, and the steam arising through this chamber not only aids thereaction but is of assistance in carrying off the lighter fractions orcomponents into fractionating tower 28 having sections designated l, 2,3, and 4. In application of the process, a greater or less number ofsections may be employed, as conditions may require. This fractionatingtower may be separate from the reaction or flash chamber, but connectedat its lower end to the upper end of the flash chamwith differentboiling ranges, and each outlet passes through a cooler 29. Thesereaction or flash chambers I8 and fractionating towers 28 with a numberof overhead outlets such as A, B,

branch pipes 41, 48 and 49, controlled respectively by valves 50, 5| and52, to the upper ends of sections I, 2 and 3 of the tower 28 so thatvapors from different tower sections may be carried directly to the pipe30 and thus by-passed directly to the condenser coil 3|.

Examples of results that can be achieved in accordance with thisinvention by the application of one pound of acid-activated clay to eachgallon of heavy oil to control the alteration of dewaxed Pennsylvania600 S. R. stock to produce relatively large amounts of high grade S. A.E. 20 motor oil and high grade Bright stock, are set ,forth in the tablebelow, which tabulates the re- 34 by a pipe 35 and removed by a pipe 36opensults oi three tests:

Orig on Test 110 Test 111 Test 112 dewaxed Penna.

S. A. E. S. A. E. 600 S. Bright S. A. E Bright Bright R. stock" stock 20stock 20 g f stock Percent en"; 34 42. 7 4s 41. a 39.0 31. s Gravity,deg. B 25. 8 28. 5 27. 0 28. 4 27.2 28. 5 27. 4 Flash, deg. F 555 475560 460 560 470 500 Fire, deg. F 625 555 630 535 630 550 670 ViscosityS. U.:

Secs. 100 deg. F i 377. 5 1, 956. 6 367. 6 1, 920. 2 343. 58 l, 904. 1Secs. 210 deg. F 159 57. 64 140. 6 56. 64 136. 0 55. 93 138. 7 Viscosityindex 99 102. 2 102. 9 99. 9 102. 4 103. 9 103. 6 Color, N. P. A. NoGreen 6 4 6 3 6 Com-adson carbon res., percent. 2. 4 0.32 15 0. 34 1. 170.31 I l. 31

ing out of the upperpart of the cabinet. The temperature to which theoil is heated in the coil l5 and in the reaction chamber 18 will dependupon the many factors well understood in the art, one of which is thecharacter of the cracking agent, if one is employed. For example, someagents cause cracking at lower temperatures than others.

The flashing action may also be aided by introducing suitable amounts ofwater, or more highly volatile hydrocarbons such as gasoline and lighterfractions, into the mixture of oil and finely divided clay and agent,-before the oil and clay enter the heating coil l5. For example, thewater or gasoline may be introduced through a pipe 3'! controlled byvalve 38 into the pipe l4, and as this new mixture is heated in the coil15, the water or highly volatile hydrocarbon will be heated to thevaporizing stage, and then when they reach the chamber l8 the Water orgasoline will pass off through the tower and carry some of the lightercomponents with them. The action in this respect is similar to thatcaused by the introduction of steam through the pipe 21, and, mayreplace or supplement the action caused by the steam admitted throughpipe 21. It may also be desirable, at times, to separately control thetemperatures in the chambers 16 and I9 and for that purpose the chamberI6 may have a direct outlet 39 at its top controlled by a valve 40, sothat some of the gases from the chamber l6 may escape directly insteadof passing through the chamber l9.

A heating medium such as a hot gas may be admitted to chamber l9 througha pipe 4| controlled by avalve 42. The pipe 30 at the top of the tower28 is provided with a control valve 43, and at a point between the Valve43 and the condenser coil 31 is connected by a pipe 44 to the transferline IT. The line IT at a point between its connection to the pip 44 andthe chamber I8, is provided with a controlling valve 45, and the pipe 44is provided with a controlling valve 46. The pipe 44 in the zone betweenthe valve 46 and the connection to the pipe 30 is connected by' Testalso yielded 4% of kerosene, 8% of gas oil, a loss of 1.3%, 2% of 63.5sec. viscosity 2 plus color nonvis neutral and 8% 0f #2 color neutral;test #111 yielded kerosene 2%, gas oil 6%, a loss of 1.4%; 2% of 77.4sec. viscosity at 100 F. 3 color, nonvis neutral, and 2% of 166.1viscosity at 100 F.; 4 /2 color neutral; test #112 yielded kerosene 4%,gas oil 10%, loss of 1.2%, 5.5% of 1 color nonvis neutral and 8.5% of 2color neutral. It will be observed that the gravity of the S. A. E. 20motor oils in all these cases is lower than is customary from purePennsylvania crude, yet the viscosity characteristics and flash and firepoints are very substantially better; the extremely high flash and firepoints of the bright stock from test #112 are notable. These testsindicate both of the important refining improvements mentioned above.

Tests 110, 111, 112 were made with the idea of making up a syntheticcrude oil which was proportionally recombined where necessary and filtered, then it was vacuum distilled in the laboratory. In the case of#110, the transfer line was directly connected to the condenser, with nosteam being used. In the case of #111, 95% by volume of water wascharged with the oil and clay, and the transfer line again connecteddirectly to the condenser. In the case of #112, the oil and clay werecharged to the heating coil while 95% by volume of water based on theoil and con verted into steam was 'charged into the base of the tower,and the overhead led to a condenser, by-passing tower sections 1, 2, 3,and 4. When the level or column height of the liquid in the reaction orflash chamber reached approximately '7 feet, the samples of overheadcondensate and bottom were proportionally combined and filtered to makethe synthetic crude for laboratory evaluation.

In the accomplishment of any refining process, manufacturing andeconomic considerations virtually make mandatory continuous rather thanbatch operation, andthis process is very satisfactory in continuousoperation. Both acid-activated clay and the chemicals disclosed hereincan be made into a finely divided state suitable for mixing with oil andpumping through a pipe still. The essential difference betweencontinuous operation in a pipe still and batch operation is that thewhole volume of oil is subjected to the maxi- 5 mum temperature in pipestill operation, while in batch operation continuous evolution ofvolatile materials occurs as the temperature is raised beyond the pointof initial volatility. Other variables, such as rate of charge, tubesize, tube length, furnace exit temperature, etc., will occur to .theminds of persons skilled in the art.

In the case of tests #110, #111 and #112 above, and in the tests whichfollow, the essential data with reference to the still used are: tubes,total length from the furnace inlet including that in heating zone andtransfer line to the point of entrance to the reaction or flash chamber,3138 inches, of which 2162 inches was in furnace heating zone, and 130inches transfer line length between furnace outlet and reaction chamber.The transfer lin discharged into a vertical reaction chamber made of 6"pipe at a point ten feet above the base, in which base was located thedischarge line and the steam flashing line. Of course, the size andlength of the reaction chamber may be varied to secure any desired timeof contact, as may also the furnace constants and variables, or thelevel carried in the reaction chamber. If desired, the reaction chambermay be arranged for auxiliary heating, as indicated in the attacheddrawin preferably down draft from the furnace itself. If virtuallycomplete volatilization of the oil from the reaction chamber is desired,the chamber may be arranged for the mechanical removal of the residualmatter including clay and chemicals.

Separation of the overhead materials into components suitable forevaluation in the laboratory /z inch 1.,

was effected by passing the overhead in succession through a 6" x 12', a6" x 12' and a 10 x12 tower, each with about 10' 6" broken tile refluxsurface and followed by a condenser and receiver, with suitable by-passarrangements so that up to four separations could be made in theoverhead. A branched connection from the transfer line directly to acombined cooler and condenser enabled icy-passing the reaction chamberand all of the towers.

Runs or tests Nos. 110, 111, 112 were made for the purpose'ofdetermining the effect of steam on the reaction. In test #110 thetransfer line was directly coupled to the condenser causing the oils tothereby by-pass the reaction chamber and towers, and the total run intoa drum on a scale where the recovery was identical with the charge. Nosteam was used except that from the clay. The transfer line temperaturewas 845 F. Test #111 was made with by-passed reaction chamber andtowers, with 845 F. transfer line temperature, using parts by volume ofwater for each parts by volume of oil which wascharged under pressureinto the oil and clay mixture through pipe 31 from an auxiliary pump(not shown). The oils under test #112 above were made with bypassedtowers, furnace exit temperature of 845 F. approximately 7 feet oillevel in reaction chamber, and close to 650 F. temperature in base ofreaction chamber, with steam, approximately 95% by volume (condensed),or by weight of the oil charged, into the base of the reaction chamber.The overhead and reaction chamber bottoms were proportionallyrecombined, filtered, vacuum distilled and tested.

The results of additional tests similar to the foregoing have beensummarized in the following table, divided endwise into two sectionswhich should be placed side by side to be read:

Variables in results from treatment of dewared Pennsylvania 600 steamrefined stock Test designation F G P N O 106 R G. C V S Acid activatedclay, lbs. per gal 1% 1% 1% 1% 1% 1% 1 1% 1 Bauxite, lbs., per gal 87%coml cuprous oxide, gms. ea. gal Oil and chem., chg. rate, gal. per hr.8.25 7.70 9. 27 9.7 11.38 18.87 9.16 13.05 14.06 13.43 Gasoline chg.rate, gal. per hr 8.00 Furnace outlet temp., deg. F. (av.) 800 820 840855 879 845 840 855 840 840 Reaction chamber base temp., deg. F 673 681673 673 693 673 694 738 721 702 Steam, per cent of oil charged 147 80. 472. 8 65. 8 17. 1 111. 0 22. 5 80. 7 70. 2

Bottoms:

Gravity, deg. B 26. 8 26. 7 27. 2 27. 7 27. 7 26. 7 27. 6 26. 5 25. 8Flash, deg. F 600 595 610 595 630 570 620 '6 8 635 625 Fire, deg. F 680675 680 670 700 660 695 '5 710 705 Viscosity, S. 188. 7 191.1 167. 2158. 8 192. 3 156. 8 185. 6 E6 218. 5 217. 1 Viscosity index 105. 6 105.3 107. 2 109. 3 110. 7 104. 8 109. 7 5 o 107.5 105. 1 Color, N. P. A. No5- 5+ 4% 4- 4- 5- 4+ m 5 5+ 6% Conradson carbon residue, per cent1.49 1. 41 1. 42 1.11 0.97 1. 43 1.09 1. 47 2. 24

Tower A overhead:

Recovered per cent of charge 40.0 44.0 38. 9 44.2 49. 3 26. 4 28. 3 55.3 28. 7 35.1 Gravity, deg. Be 27. 8 27. 7 v 28. 2 28. 0 27. 9 28. 2 27.3 28. 1 27. 3 27. 4 Flash, deg. F. 500 495 455 480 485 500 520 365 515515 Fire, deg. F 575 575 545 570 575 575 605 570 605 600 Viscosity, S.U. 210 F 67. 92 68. 75 58. 67 64. 26 64. 5 63. 68 73. 72 61. 75 75. 5971. 74 Viscosity index" 98. 4 99. 6. 103. 2 99. 2 101. 3 98. 4 100. 7106. 9 98. 6 97. 4

Tower B overhead:

Recovered per cent of charge 8.0 15. 4 9. 7 16.5 21. 3 8. 4 17.6 17. 729. 3 9. 6 Gravity, deg. B 27.7 27. 8 28. 1 28.1 28. 3 27. 9 27. 8 28. 627. 7 27. 8 Flash, deg. F... 390 365 365 375 410 410 220 400 410 Fire,deg. F 495 435 430 445 460 495 400 495 485 Viscosity, S. U. 210 F" 57.02 44. 3 44. 37 44. 1 44. 66 54. 01 41. 85 55. 69 50. 06 Viscosity index102- 7 98. 7 102. 0 108. 4 96. 0 104. 6 111. 6 103. 6 99. 7

Tower C. overhead: Recovered per cent of charge 3 8 g 7. 9 24. 0 3Gravity, deg. B N Q a! 32.1 32. 9 Flash, deg. g E i Q E 220 Q a a Fire,deg. F co on a: pa o 255 pm 210 pa n Condensate:

Recovered per cent of charge 22.0 19 8 18. 8 25.1 25 8 6 5 23. 9 Gaso.18.3 13.1 Gravity, deg. B 35. 3 37 6 38. 1 40. 0 40 2 46 3 38. 6 56. 837. 3 37. 1

Gasoline separately heated and charged to base of reaction chamber inthis test.

Test designation T W 104 101 103 107 108 G. E G. H. G.I

Acid activated clay, lbs. per gal Bauxite, lbs., per gal 87% com]cuprous oxide, gms. ea. gaL Oil and chem., chg. rate, gal. per hrGasoline chg. rate, gal. per hr Furnace outlet temp., deg. F. (av.)Reaction chamber base temp., deg. F. Steam, per cent of oil chargedBottoms:

Gravity, deg. B5 242 n 25.8 25.5 25.4 25.9 25.9 25.5 25.2 25.5

Flash, deg. 535 .25 570 580 580 550 570 500 505 505 Fire, deg. F 7105,53 550 570 555 535 555 575 590 590 Viscosity, s. U. 210 259.5 ugg152.5 179.3 175.2 137.1 157.5 221 244.4 227 Viscosity index 101.7 555.104.3 104.9 103.4 104.8 105.2 105.0 108.7 105.5

Color, N. P. A. No Green BB 5-- 5- 5+ 5- 4 4%4- 5 5- Conradson carbonresidue, per cent 4. 1.58 1.53 1. 76' 1.42 1.45 1.65 1.71 1.63

Tower A overhead:

Recovered per cent of charge 32.0 40.2 29.7 38.9 32.3 14.2 20.0 23.547.7 42.2

Gravity, deg. B 25.8 27.5 28.3 28.0 28.1 23.4 28.4 27.5 27.5 27.8

Flash, deg. 520 505 485 .490 485 475 505 525 505 515 Fire, deg. F 510595 555 575 555 540 580 515 5 590 500 Viscosity, s. U.@210F 78.4 70.5950.5 54.2 50.5 57.3 57.4 75.0 71.2 72.08

Viscosity index 95.4 103.7 98.3 100.1 100.5 99.5 102.4 98.5 99.1 99.7

Tower B overhead:

Recovered percent'of charge 27.8 28.3 4.2 7.5 3,1 2.9 7.0 12.8 7.0 9.6

Gravity, deg. B5 27.8 27.7 27.7 27.8 27.8 27.8 28.3 28.2 27.9 27.9

Flash, deg. F... 415 390 415 350 355 410 440 415 420 410 Fire, deg. F505 475 470 420 430 455 505 515 500 495 Viscosity, s. r 55.8 52.29 45.0841.2 41.4 45. 37 49.5 53.4 49.5 49.1

Viscosity index 100.3 103.2 95.4 90.8 97.2 96.2 102.6 100.4 98.4 100.6

' Tower 0. overhead: 8 E

Recovered per cent of charge g g 5.7 5.6 3.7 7.9 6. 12.2 10.2 3.8

Gravity, deg. B 5 =1 31.0 32.0 31.0 31.4 29.1 33.1 32.3 32.9

Flash, deg. F E; Q 235 210 250 225 250 85 110 115 Fire, deg. F to to 270250 290 270 320 100 145 145 Condensate: V

Recovered per cent of charge 13.4 22.5 6.3 6.0 5.3 6.4 10.5 Gaso. Gaso.Gaso- Gravity, deg. B 39.7 37.8 44.5 45.1 44.8 44.2 40.8 60.8 52.7 53.2

Impure.

In the above two section table Bottoms refers charge rate. Duringoperation a liquid level of to the filtered oil recovered from thematerial approximately 7' was maintained in the reaction extracted fromthe base of the reaction chamber; tower, although this level was variedat difierent Tower A overhead, to the material withdrawn times. from thecooler attached to the first overhead The quantities of clay used pergallon of oil collection chamber; Tower B overhead, to the 40 charged inthese tests varied from /2 pound to material similarly Withdrawn fromthe second 1 /4 p unds. ut le er n greater am unt n overhead collectionchamber; Tower C overbe used depending upon the oil treated and rehead,to material from the third chamber; and sults desired. Itwas discoveredthat one P nd Condensate, to the material withdrawn from was close tothe optimum for this 011. The nec-. the condenser receiver. In somecases tower C essary quantity of clay required is less usually wasbypassed, in which case the proper notation than 25% of the weightof'the oil being treated. was made. The difierence between the Furnaceysfrom different sources or methods f repoutlet temperature and thReaction chamber aration vary markedly in their efiectiveness. The basetemperature, is the temperature range exnecessary q n ity of a clay forany iven il is isting in the oil and clay being treated. Steam,determined readily by experimentation, taking percent of oil charged mens v l of wat nto consideration the quantity of vaporized main percentreferred to the volume of the oil terial desired, quality and quantityof residual charged, changed into steam and fed into the p oductsdesired, a d temperature d t e'as base of the reaction chamber. Thevarious test well s other governing ctors involved. Q ite designationsrefer to those common in the induswide variation in results can beobtained t a try. In test Q no flashing steam was used except ivenquantity of acid activated c ay y varying that in the clay. time ofcontact and temperature. .The transfer In an example of the operation ofa unit in ne e p atu is egarded to be of prima accordance with thisinvention, a mixture of acid p nce. a soa g ti and temperature activateday a d il was arged throu h the secondary importance. The transfer linetemheater and there heated to the desired temperatures varied from800-879 F. insofar as the perature. This mixture was discharged into thedata herewith is concerned. The temperatures reaction tower maintainedat substantially atto be used must be determined experimentallymospheric pressure. At the same time, steam for different oils and endresults and are usually from the steam generator, in a Volume ratiorelalower than t e above e for naphthenic 01 tive to the 011 charge, wasintroduced into the The catalyst used in he x p for which bottom of thereaction tower. The towers, predata is iven in the tables herein,consisted of viously, had been brought to the desired tem- Super Filtrol(sulfuric acid activated clay). perature by the injection of superheatedsteam. WF banXite and hydrochloric acid activated The charging of steamto the towers was conclays were used, but it was found in the worktinued until the unit was on stream. When .the w1th bauxite that thismateria1 has too high a; unit was on stream the steam at the bottoms ofspecific g i y. to be readily pumped through a towers Nos. 2, 3, and 4were, generally speaking, pipe still without continuous risk of cloggingat cut on, and the charge of oil, clay and steam in some point in theapparatus and it was found the reaction vessel wasmaintained at thedesired necessary to use it in conjunction with Super Filtrol. Wherebauxite was used with Super Filtrol, this is indicated on the table.None of the work on the hydrochloric acid clays is reported in thetables included herein, this work having been done at an earlier time.The German Tonsil clay was found to be more effective than Super Filtrolon a dry basis. Work was also done with four samples of hydrochloricacid activated clays manufactured by an American company and normallyused in the decolorization of fatty oils. In this work it was found thatone of these clays which was least eifective for the treatment of fattyoil was most effective from the standpoint of the process. that thegreater efiiciency of the Tonsil clay was traceable to the presence ofimpurities in the clay which serve to act as desulphurizing agents andthereby reduce the normal clay requirements of the reaction. Inconnection with this, it was observed that the clay requirements of thprocess can be materially reduced by incorporating in the reactionmixture a small proportion of any one of the large group of metalliccompounds which form stable compounds with sulphur or other impurities.The quantity of desulphuriz-. ing metal used appears to be quitecritical. This is particularly so in the case of copper, and thequantity used must be controlled within narrow limits in order to obtainmaximum efficiency and effectiveness.

Synthetic crudes of these three tests were made, filtered and vacuumstilled in the labora. tory to yield the results shown on the tablesincluded herein.

It mi ht be mentioned herethat for the purpose of separating spentcatalyst from the oil,

the mixture of oil and spent catalyst was filtered through a plate andframe filter press although a y suitable method may be used.

A consideration of the results obtained indicates that two primaryeffects take place, namely, degradation and volatilization of unstablecomponents, and a chemical alteration and increased stabilization ofstable components, probably by a reaction such as cyclization orhydrogenation. Thus, among others, two important refining improvementsresult:

1. Products having both improved viscosity index. and improved physicalcharacteristics are produced.

. 2 The, p oduction of large quantities, of lightbodied lubricants ofhigh quality from less useful heavy-bodied oils becomes feasible,together with the production of residual heavy-bodied oils which hav anextremely high quality.

Insofar as known, no other means of accomplishing these results areavailable. In making this statement, it is recognized that the resultsobtained by the hydrogenation of. lubricating oils might be cited as aqualification.

The process is equally applicable to paraffin base, naphthene base, andmixed base oils. The effectiveness, when considered in the light ofactual improvement, say, in viscosity index, is greater in the case ofthe naphthene base oils because there the chances of improving viscosityindex are greater. In this connection, som of the work on straight zeroviscosity index naphthene base oils resulted in a material with aviscosity index of about 40 to 44. On furfural refined naphthem'c oilhaving an initial viscosity index of 63, a carbon residue of 0.09%, asulphur of 0.22% and a No. 3 color, with a purplish bloom, theapplication of the process resulted in a product having a viscosityindex of 78, a carbon This indicates residue of 0.08%, a sulphur of0.12% and a 1% color, with a yellow-green bloom. These tests do notrepresent the feasible upper limits obtainable with this improvedprocess, but they in.v dicate the practicability of the process.

The examples explained above lead one to conclude that the best possibleoils for internal combustion engines can be made by means of theapplication of thi process to naphthenic oils, because the low pour andlow carbon tests are retained, While high viscosity index, high flashand stability not originally present are produced in the oil. Theforegoing remarks are also applicable to mixed base oils which can bereadily converted into high-grade products by the application of theprocess.

Residual oils resulting from the high temperature treatment ofpetroleum, petroleum products, or other hydrocarbon materials, usuallyhave a foul, obnoxious odor, and are unstable. Treatment by the processherein disclosed eliminates most of these objectionable characteristics,but it was discovered that certain residual oils were not deodorizedsufliciently by this means to be marketable, with economically feasiblequantities of acid activated clay. Experimentation led to the discoverythat certain impurities existing in hydrocarbon materials, probablyforms of oxygen, sulfur, halogen, nitrogen, or other impurity, act asclay poisons, hence if a method could be devised for neutralizing oreliminating these products, marked economies in clay quantities requiredcould be effected.

Investigation of the impurity problem using an Onondaga crude oil as theworking agent, led to the discovery that certain metals, preferably inthe form of compounds, including metallic salts, when used in connectionwith acid activated clay at temperatures substantially above 400 F.enabled the elimination of much of the undesirable matter from theresidual oil, the undesired materials evolving with the distillate orbeing removed with the clay. In some cases temperatures above 740 F.were used. Among the impurities evolved with different metalliccompounds or salts used in this connection were sulfur flowers, sulfurdi-. oxide gas, hydrogen sulfide, ammonia gas, amines, nitrogen oxide,alcohols and quantities of unidentified, rank smelling, choking, gaseousmate.- rials and small amounts of unidentified white and pink-whitesolids. Further work with solvent refined oils led to the detection ofodors of nitrobenzene, furfural and phenol in the vapors dis.- tilledoff of various oils.

With reference to the common heavy metals usually in the form of oxidesor salts, copper,

zinc, nickel, and iron gave excellent color results in acid activatedclay treatments of Onondaga crude oil; all of the heavy metals tested,including lead, manganese, and chromium as well, asv

copper, nickel, zinc, and iron produced odor improvement. As a check onother oils, copper oxide was tried with excellent results on a widevariety of oils, both paraffinic, mixed base and asphaltic orso-called-naphthenic oils, showing that the process is applicablegenerally, and permitting the choice of the metal best fitting theparticular oil being investigated. In several cases, mixtures of metalswere-used efiectivelyto secure the beneficial effects resulting from thecombination.

Because of the wide choice of metal compounds and salts available, andthe fact that materials.

remaining with the oil because of the-treatment, such as halogencompounds, phosphorus compounds, sulfur compounds, nitrogen compoundsand oxygen compounds are known definitely to affect film strength andoiliness characteristics of lubricants, a wide variety of coppercompounds Was used with the clay on Onondaga crude oil to demonstratethe effect of varying the compound or salt used. Onondaga crude oilgives a negative chlorin indication by means of the commonly used flametest with hot copper wire, showing virtual absence of chlorine in thecrude oil itself; when treated with cuprous chloride in connection withacid activated clay, among other substances, large amounts ofhydrochloric acid gas were evolved, but the filtered residual oil stillgave a negative chlorine test by means of the same copper wire flametest; when treated with cupric chloride, however, in addition to thelarge amounts of hydrochloric acid gas evolved, the liltered residualoil gave a positive chlorine test, indicating chlorine remaining in theoil; in neither of the latter cases were flowers of sulfur condensed inthe condenser tube but a heavy yellow, oily substance condensing in thetube was noticed in both cases.

Copper sulfate used in a similar manner showed heavy flowers of sulfurdeposits in the condenser tube, and heavy evolution of sulfur dioxidegas,

as well as other impurities. With cupric acetate, acetic acid fumesWithout deposit of flowers of sulfur in the condenser tube were noted;with cupric phosphate the fume was led through water before examination,nevertheless heavy deposits of flowers of sulfur were noted in thecondenser tube, and hydrogen sulfide was noticed in the fume bath; withcupric chromate, heavy flowers of sulfur deposits were noted in thecondenser tube, together with heavy evolution of fumes, and arelativelyplean appearing distillate; cupric hydroxide, cuprous oxide,cupric oxide, cupric carbonate, cupric hydroxide-carbonate, reactivecopper. silicate and cupric-nickelous hydroxide, each in combinationwith acid activated clay permitted evolution of flowers of sulfur andyielded satisfactory residual products. In connection with nitrates,nitrogen oxide as well as both ammonia gas and amines were detectedamong the impurities evolved. Combinations of metallic salts have beenused and may be used if desired.

It is quite within the scope of this disclosure to use combinationseither of metals, metals and salts, or salts of metals, in connectionwith acid activated clay or clays, depending upon results desired.Inclusion of a portion of the acidic radical in the residual oil alsomay decide the choice.

In preventing the poisoning of the clay by the impurities of thehydrocarbon under treatment, the metals in pure metallic subdivided formdo not appear to be as satisfactory in action as are the compounds ofthe metals, and particularly the salts of the metals.

It will be understood that various changes in the details which havebeen herein described in order to explain the nature of the invention,may be made by those skilled in the art, within the principle and scopeof the invention, as expressed in the appended claims.

I claim:

l. In the conversion, of a naphthenic petroleum oil, to obtain arelatively high yield of light-bodied lubricating components of superiorphysical characteristics, such as a high viscosity index, high flash andstability, the improved method which comprises mixing said oil, while ata temperature below its natural cracking temperature, with unspent,acid-activated clay to provide a pumpable mixture in which the clay issuspended in the oil and amounts to approximately between one-half poundand one and onequarter pounds per gallon of oil, passing said mixture asa stream in liquid phase and upwardly through an ascending heatingpassage and then into a reaction chamber, incorporating water in themixture before it completes its ascent in said passage equal toapproximately per cent of the oil, heating the mixture while moving insaid passage approximately to cracking temperature below approximately900 degrees F., flashing the heated mixture with a vapor in said chamberat cracking temperature, separating the overhead vapors from the bottomscon taining the clay, and condensing the overhead vapors.

2. In the conversion of a naphthenic petroleum oil, to obtain arelatively high yield of lightbodied lubricating components of superiorphysical characteristics, such as a high viscosity index, high flash andstability, the improved meth; od which comprises mixing said oil, whileat a temperature below its natural cracking temperature, with unspent,acid-activated clay to provide a pumpable mixture in which the clayissuspended in the oil and amounts to approxi mately between one-halfpound and one and onequarter pounds per gallon of oil, passing saidmixture as a stream in liquid phase and upwardly through an ascendingheating passage and then into a reaction chamber, incorporating in themixture before it completes its ascent in said passage, a flashing agentin liquid phase which vaporizes at a temperature lower than that towhich the mixture is heated before it reaches the top of said ascendingpassage, equal to approximately 95 per cent of the oil, heating themixture while movin in said passage approximately to crackingtemperature below approximately 900 degrees F., flashing the heatedmixture with a vapor in said chamber at cracking temperature, separatingthe overhead vapors from the bottoms containing the clay, and condensingthe overhead vapors.

3. In the conversion of a naphthenic petroleum oil, to obtain arelatively high yield of lightbodied lubricating components of superiorphysical characteristics, such as a high viscosity index, high 7 flashand stability, .the improved method which comprises mixing said oil,While at a temperature below its natural cracking temperature, withunspent, acid-activated clay and a finely divided agent containing ametal to provide a pumpable mixture in which the clay and finely dividedagent are suspended in the oil an amount to approximately betweenone-half pound and one and one-quarter pounds per gallon of oil, passingsaid mixture as a stream in liquid phase and upwardly through anascending heating passage, and then into a reaction chamber,incorporating water in the mixture before it completes its ascent insaid passage equal to approximately 95 per cent of the oil, heating themixture while moving in said passage approximately to crackingtemperature below approximately 900 degrees F., flashing the heatedmixture with a Vapor in said chamber at cracking temperature, separatingthe overhead vapors from the bottoms containing the clay and finelydivided agent, and condensing the overhead vapors.

4. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubrieating components with relatively highviscosity index, high flash and stability, the improved method whichcomprises mixing said oil while at a temperature below its naturalcracking temperature with unspent, acid-activated clay, to provide apumpable mixture in which the clay is suspended in the oil and amountsto at least approximately one-half pound of clay per gallon of oil,passing said mixture as a stream in liquid phase upwardly in anascending heating passage, heating the stream in said passage to thedesired conversion temperature and below approximately 900 degree F.,incorporating a readily volatilizable liquid in the mixture of saidstream before the stream completes its ascent and before the temperatureis raised to the maximum extent, flashing the heated mixture of saidstream after it reaches said desired conversion temperature to createvapors, separating the vapors from the bottoms containing the clay, andcondensing the vapors.

5. In the conversion of a naphthenic petrobum oil, to obtain arelatively high yield of lightbodied lubricating components withrelatively high viscosity index, high flash and stability, the improvedmethod which'comprises mixing said oil, while at a temperature below itsnatural cracking temperature, with unspent, acid-activated clay toprovide a pumpable mixture in which the clay is suspended in the oil andamounts to at least approximately one-half pound of clay for each gallonof oil, passing said mixture as a stream in liquid phase upwardlythrough an ascending passage and then into a reaction chamber,incorporating water in the mixture of said stream before the streamcompletes its ascent in said passage, heating the mixture moving in saidpassage approximately to a desired conversion temperature and belowapproximately 900 degrees F., flashing the heated mixture in saidchamber to create vapors, separating the overhead vapors from thebottoms containing the clay, and condensing the overhead vapors.

6. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components having a relatively highviscosity index, high flash and stability, the improved method whichcomprises mixing said oil while at a temperature below its natural;cracking temperature with unspent, acid-activated clay to provide apumpable mixture in which the clay amounts to at least approximatelyone-half pound per gallon of oil, passing said mixture as a stream inliquid phase upwardly in'a confined passage and then into a reactionchamber, incorporating in said stream before it completes its ascent insaid passage a flashing agent in liquid phase, which vaporizes at atemperature below that to which the stream is heated before it completesit ascent in said passage, heating the mixture moving in said passage toa desired conversion temperature less than approximately 900 degrees F.,flashing the heated mixture in said chamber to create vapors, separatingsaid vapors from the bottoms containing the clay, and condensing theoverhead vapors.

7. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components of superior physicalcharacteristics, such as a high viscosity index, high flash andstability, the improved method which comprises mixing said oil, while ata temperature below its natural cracking temperature, with unspent,acid-activated clay-to provide a pumpable mixture in which the clay issuspended in the oil and amounts to approximately between one-half poundand one and one-quarter pounds per gallon of oil, passing said mixtureas a stream in liquid phase and upwardly through an ascending heatingpassage and then into a reaction chamber, incorporating water in themixture before it completes its ascent in said passage, heating themixture while moving in said passage approximately to crackingtemperature below approximately 900 degrees F., flashing the heatedmixture in said chamber at cracking temperature, separating the overheadvapors from the bottoms containing the clay, and condensing the overheadvapors.

8. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components with relatively highviscosity index, high flash and stability, the improved method whichcomprises mixing said oil while at a temperature below its naturalcracking temperature with unspent, acid-activated clay, to provide apumpable mixture in which the clay is suspended in the oil, passing saidmixture as a stream in liquid phase upwardly in an ascending heatingpassage, heating the stream in said passage to the desired conversiontemperature and below approximately 900 degrees F., incorporating areadily volatilizable liquid in the mixture of said stream before thestream completes its ascent and before the temperature is raised to themaximum extent, flashing the heated mixture of said stream after itreaches said desired conversion temperature to create vapors, separatingthe vapors from the bottoms containing th clay, and condensing thevapors.

9. In the conversion of a naphthenic petroleum oil, to obtain arelatively high yield of lightbodied lubricating components withrelatively high viscosity index, high flash and stability, the improvedmethod which comprises mixing said oil, while at a temperature below itsnatural cracking temperature, with unspent, acid-activated clay toprovide a pumpable mixture in which the clay is suspended in the oil,passing said mixture as a stream in liquid phase upwardly through anascending passage and then into a. reaction chamber, incorporating waterin the mixture of said stream before the stream completes its ascent insaid passage, heating the mixture moving in said passage approximatelyto a desired conversion temperature and below approximately 900 degreesF., flashing the heated mixture in said chamber to create vapors,separating the overhead vapors from the bottoms containing the clay, andcondensing the overhead vapors.

10. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components with relatively highviscosity index, high flash and stability, the improved method whichcomprises mixing said 011 while at a temperature below its naturalcracking temperature with unspent, acid-activated clay and a metallicoxide, to provide a pumpable mixture in which the clay is suspended inthe oil and amounts to at least approximately one-half pound of clay pergallon of oil, passing said mixture as a stream in liquid phase upwardlyin an ascending heating passage, heating the stream in said passage tothe desired conversion temperature and below approximately 900 degreesF., incorporating a readily volatilizable liquid in the mixture of saidstream before the stream completes itsascent and before the temperatureis raised to the maximum extent, flashing the heated mixture of saidstream after it reaches said desired conversion temperature to createvapors, separating the vapors from the bottoms containing the clay, andcondensing the vapors.

11. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components of superior physicalcharacteristics, such as a high viscosity index, high flash andstability, the improved method which comprises mixing said oil, while ata temperature below its natural cracking temperature, with unspent,acid-activated clay' to provide a pumpable mixture in which the clay issuspended in the oil and amounts to approximately between one-half poundand one and one-quarter pounds per gallon of oil, passing said mixtureas a stream in liquid phase and upwardly through an ascending heatingpassage and then into a reaction chamber, incorporating water in themixture before it completes its ascent in said passage equal toapproximately 95 per cent of the oil, heating the mixture while movingin said passage approximately to cracking temperature belowapproximately 900 degrees F., flashing the heated mixture with a vaporin said chamber at cracking temperature, separating the overhead vaporsfrom the bottoms containing the clay, and condensing the overheadvapors.

12. In the conversion of a petroleum oil, to obtain a relatively highyield of light-bodied lubricating components with relatively highviscosity index, high flash and stability, the improved method whichcomprises mixing said oil while at a temperature below its naturalcracking temperature with unspent, acid-activated clay, to provide apumpable mixture in which the clay is suspended in the oil, passing saidmixture as a stream in liquid phase upwardly in a heating passage,heating the stream in said passage to the desired conversion temperatureand below approximately 900 degrees F., incorporating a readilyvolatilizable liquid in the mixture of said stream before the streamcompletes its ascent and before the temperature is raised to the maximumextent, flashing the heated mixture of said stream with steam in anamount which before conversion from water to steam was at least percentby volume of the oil, after it reaches said desired conversiontemperature to create vapors, separating the vapors from the bottomscontaining the clay, and condensing the vapors.

WILLIAM ALVAH SMITH.

